395 research outputs found
Derivative-Based Trapezoid Rule for the Riemann-Stieltjes Integral
The derivative-based trapezoid rule for the Riemann-Stieltjes integral is presented which uses 2 derivative values at the endpoints. This kind of quadrature rule obtains an increase of two orders of precision over the trapezoid rule for the Riemann-Stieltjes integral and the error term is investigated. At last, the rationality of the generalization of derivative-based trapezoid rule for Riemann-Stieltjes integral is demonstrated
Interleukin-18 enhances vascular calcification and osteogenic differentiation of vascular smooth muscle cells through TRPM7 channel activation
Objective—Vascular calcification (VC) is an important predictor of cardiovascular morbidity and mortality. Osteogenic differentiation of vascular smooth muscle cells (VSMCs) is a key mechanism of VC. Recent studies show that IL-18 (interleukin-18) favors VC while TRPM7 (transient receptor potential melastatin 7) channel upregulation inhibits VC. However, the relationship between IL-18 and TRPM7 is unclear. We questioned whether IL-18 enhances VC and osteogenic differentiation of VSMCs through TRPM7 channel activation.
Approach and Results—Coronary artery calcification and serum IL-18 were measured in patients by computed tomographic scanning and enzyme-linked immunosorbent assay, respectively. Primary rat VSMCs calcification were induced by high inorganic phosphate and exposed to IL-18. VSMCs were also treated with TRPM7 antagonist 2-aminoethoxy-diphenylborate or TRPM7 small interfering RNA to block TRPM7 channel activity and expression. TRPM7 currents were recorded by patch-clamp. Human studies showed that serum IL-18 levels were positively associated with coronary artery calcium scores (r=0.91; P<0.001). In VSMCs, IL-18 significantly decreased expression of contractile markers α-smooth muscle actin, smooth muscle 22 α, and increased calcium deposition, alkaline phosphatase activity, and expression of osteogenic differentiation markers bone morphogenetic protein-2, Runx2, and osteocalcin (P<0.05). IL-18 increased TRPM7 expression through ERK1/2 signaling activation, and TRPM7 currents were augmented by IL-18 treatment. Inhibition of TRPM7 channel by 2-aminoethoxy-diphenylborate or TRPM7 small interfering RNA prevented IL-18–enhanced osteogenic differentiation and VSMCs calcification.
Conclusions—These findings suggest that coronary artery calcification is associated with increased IL-18 levels. IL-18 enhances VSMCs osteogenic differentiation and subsequent VC induced by β-glycerophosphate via TRPM7 channel activation. Accordingly, IL-18 may contribute to VC in proinflammatory conditions
Nonlinear vibration of rectangular plate under the parametric excitation
In this paper, the dynamic behavior of rectangular plate under the in-plane load is studied. The partial differential equation based on the mechanical model is established, which will be deduced into two ordinary differential equations by use of Galerkin method. The existence of 1/2 harmonic solutions of the dynamical system applying the harmonic balance method is analyzed. The amplitude-frequency relationship is found, and the stability of solutions is investigated. The stable zone of dynamical system is determined
A Case of Congenital Isolated Adrenocorticotropic Hormone Deficiency Caused by Two Novel Mutations in the TBX19 Gene
Congenital isolated adrenocorticotropic hormone (ACTH) deficiency (CIAD) is a rare disorder which can result in 20% mortality in the neonatal period if misdiagnosed. A 2 years and 7 months old boy was hospitalized many times because of recurrent hypoglycemia. On initial physical examination, the patient showed special appearance and indications of fast growth (≥P97). Laboratory investigations revealed low levels of ACTH and cortisol in his plasma. Except thyroid-stimulating hormone, the anterior pituitary hormone concentrations were normal. Molecular data showed compound heterozygosity for two novel mutations in the TBX19 gene (encoding the transcription factor T-Box 19). Mutation c.205C>T was inherited from mother and the fragment deletion (from g.168,247,374 to g.168,278,264) was from father. Hydrocortisone replacement therapy was effective. We reported two novel TBX19 mutations, expanding the mutation spectrum of this disorder, in a CIAD patient who presented with special appearance, signs of fast growth, and thyroid-stimulating hormone derangement. In addition, for avoiding misdiagnosis, criterion for ACTH and cortisol detection of CIAD should be established
Efficacy and Safety of Modified Banxia Xiexin Decoction (Pinellia Decoction for Draining the Heart) for Gastroesophageal Reflux Disease in Adults: A Systematic Review and Meta-Analysis
Effects of selected socio-demographic characteristics on nutrition knowledge and eating behavior of elementary students in two provinces in China
Background: National and international child health surveys have indicated an increase in childhood obesity in China. The increase has been attributed to a rising standard of living, increasing availability of unhealthy foods, and a lack of knowledge about healthy diet. The objective of this study was to assess the effect of selected sociodemographic characteristics on the BMI, nutrition knowledge, and eating behavior of elementary school children. Methods: Multistage stratified cluster sampling was used. Information on demographics, nutrition knowledge, and eating behavior was gathered by means of questionnaires. The schools’ doctors provided the height and weight data. The study was set in one economically advantaged and one economically disadvantaged province in China. The participants were Grade 3 students, ages 8–10 years (N = 3922). Results: A cluster analysis identified four socio-demographic variables distinguished by parental education and family living arrangement. A one-way ANOVA compared differences among the clusters in BMI, child nutrition knowledge, and child eating behavior. Students in the cluster with lowest parent education level had the lowest nutrition knowledge scores and eating behavior scores. There was no significant benefit from college education versus high school education of parents in the other three clusters. BMI was not affected by parent education level. Conclusion: The nutrition status of elementary school age children will benefit most by increasing the general level of education for those adults who are presently least educated
Genome-wide DNA methylation analysis of pulmonary function in middle and old-aged Chinese monozygotic twins
Background Previous studies have determined the epigenetic association between DNA methylation and pulmonary function among various ethnics, whereas this association is largely unknown in Chinese adults. Thus, we aimed to explore epigenetic relationships between genome-wide DNA methylation levels and pulmonary function among middle-aged Chinese monozygotic twins. Methods The monozygotic twin sample was drawn from the Qingdao Twin Registry. Pulmonary function was measured by three parameters including forced expiratory volume the first second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio. Linear mixed effect model was used to regress the methylation level of CpG sites on pulmonary function. After that, we applied Genomic Regions Enrichment of Annotations Tool (GREAT) to predict the genomic regions enrichment, and used comb-p python library to detect differentially methylated regions (DMRs). Gene expression analysis was conducted to validate the results of differentially methylated analyses. Results We identified 112 CpG sites with the level of P < 1 x 10(-4) which were annotated to 40 genes. We identified 12 common enriched pathways of three pulmonary function parameters. We detected 39 DMRs located at 23 genes, of which PRDM1 was related to decreased pulmonary function, and MPL, LTB4R2, and EPHB3 were related to increased pulmonary function. The gene expression analyses validated DIP2C, ASB2, SLC6A5, and GAS6 related to decreased pulmonary function. Conclusion Our DNA methylation sequencing analysis on identical twins provides new references for the epigenetic regulation on pulmonary function. Several CpG sites, genes, biological pathways and DMRs are considered as possible crucial to pulmonary function.Peer reviewe
Genome-wide DNA methylation and gene expression analyses in monozygotic twins identify potential biomarkers of depression
Depression is currently the leading cause of disability around the world. We conducted an epigenome-wide association study (EWAS) in a sample of 58 depression score-discordant monozygotic twin pairs, aiming to detect specific epigenetic variants potentially related to depression and further integrate with gene expression profile data. Association between the methylation level of each CpG site and depression score was tested by applying a linear mixed effect model. Weighted gene co-expression network analysis (WGCNA) was performed for gene expression data. The association of DNA methylation levels of 66 CpG sites with depression score reached the level of P < 1 x 10(-4). These top CpG sites were located at 34 genes, especially PTPRN2, HES5, GATA2, PRDM7, and KCNIP1. Many ontology enrichments were highlighted, including Notch signaling pathway, Huntington disease, p53 pathway by glucose deprivation, hedgehog signaling pathway, DNA binding, and nucleic acid metabolic process. We detected 19 differentially methylated regions (DMRs), some of which were located at GRIK2, DGKA, and NIPA2. While integrating with gene expression data, HELZ2, PTPRN2, GATA2, and ZNF624 were differentially expressed. In WGCNA, one specific module was positively correlated with depression score (r = 0.62, P = 0.002). Some common genes (including BMP2, PRDM7, KCNIP1, and GRIK2) and enrichment terms (including complement and coagulation cascades pathway, DNA binding, neuron fate specification, glial cell differentiation, and thyroid gland development) were both identified in methylation analysis and WGCNA. Our study identifies specific epigenetic variations which are significantly involved in regions, functional genes, biological function, and pathways that mediate depression disorder.Peer reviewe
Preparation and evaluation of PEGylated phospholipid membrane coated layered double hydroxide nanoparticles
AbstractThe aim of the present study was to develop layered double hydroxide (LDH) nanoparticles coated with PEGylated phospholipid membrane. By comparing the size distribution and zeta potential, the weight ratio of LDH to lipid materials which constitute the outside membrane was identified as 2:1. Transmission electron microscopy photographs confirmed the core-shell structure of PEGylated phospholipid membrane coated LDH (PEG-PLDH) nanoparticles, and cell cytotoxicity assay showed their good cell viability on Hela and BALB/C-3T3 cells over the concentration range from 0.5 to 50 μg/mL
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